(Reuters) - From the elaborate details of a Japanese state visit to the more mundane question of how much face-time to give each of his Asian hosts, President Barack Obama's aides spent months meticulously scripting his four-country tour of the region.

But as the week-long trip wrapped up on Tuesday it was clear that, while Obama scored points with skeptical allies simply by showing up, not everything followed the White House plan.

The U.S. president's clear aim was to demonstrate that his long-promised strategic shift towards Asia and the Pacific, widely seen as aimed at countering China's rising influence, was real. Early reviews from the region were mixed.

"The key is what happens next," said Michael Kugelman, an Asia expert at the Wilson Center think-tank in Washington. "If the U.S. starts dragging its feet, the skeptical whispers could begin anew."

Japan, Obama's first stop, set the tone for a glass-half-full/glass-half-empty dynamic that characterized the trip.

He was notably unable to announce a two-way trade deal with Japan, despite an informal "sushi summit" with Prime Minister Shinzo Abe and marathon last-ditch negotiations, raising questions over the momentum behind a broader trans-Pacific pact.

Things went so badly the two sides had to delay issuing a summit-ending joint communiqué - normally a mere formality between close allies - until just before Obama left.

In the end, they lauded progress towards a deal, perhaps the best that could have been hoped for given the bitter domestic debates over trade in both countries.

More important from the Japanese perspective was Obama's assurance that Washington would come to Tokyo's defense - including of tiny islands at the heart of a territorial dispute with China - coupled with a U.S. warning to Beijing against trying to change the status quo by force.

Kunihiko Miyake, a former Japanese diplomat, said Obama's statement that their mutual security treaty covers the disputed isles, known as the Senkaku in Japan and the Diaoyu in China, was "more than enough" for Tokyo.

BALANCING ACT

The risk of Obama's rhetoric in Japan - as well as at other stops on his journey through Asia, where several allies face maritime disputes with China - was of antagonizing Beijing and damaging U.S. ties with the world's second-biggest economy.

Analysts mostly agreed that Obama got the balance right by assuring America's friends of U.S. security assistance while insisting that Washington was not trying to contain China.

China called on the United States and Japan to abandon their "Cold War mentality" but was mostly muted about rest of the trip, although some experts cautioned Beijing's response might only become clear in the coming weeks or months.

Shi Yinhong, director of the Center for American Studies at Renmin University in Beijing, said the Obama administration probably felt its message of deterrence to China and reassurance to Japan and other allies was delivered successfully.

"But if we want to know if the trip seriously harmed U.S.-China relations and damaged to the United States' strategic and economic interests, we can only draw a question mark," Shi said.

Near the end of the trip, one Chinese official implied that American's interest in the region could be fleeting, as even some allies fear, while Beijing's engagement would be constant.

"If you come or do not come, we will be here," said Chinese foreign ministry spokesman Qin Gang.

FOREIGN POLICY CRITICISM

Obama's first Asia trip of his second term also comes at a time when his broader foreign policy record is facing criticism, including over his response to the Syrian civil war and a faltering Israeli-Palestinian peace effort.

Skeptics among the United States' friends in the region fear the faltering "pivot", meant to refocus America's attention on the dynamic economies of the Pacific Rim, could be undone by the competing pull of events in Europe and the Middle East.

It could hardly have been lost on Obama's hosts that he was often pulled off-script to focus on the crisis in Ukraine.

The issue figured prominently in all four news conferences he gave in the region, and he also used the time to rally European leaders behind a new round of sanctions against Russia.

But seeking to dispel any doubts about Washington's staying power in Asia, Obama told a news conference in Manila on Monday:

"Our alliances in the Asia Pacific have never been stronger; I can say that unequivocally."

NO NEW IDEAS

In South Korea, Obama offered poignant words of condolence over the scores killed in an April 16 ferry disaster and also expressed solidarity over Seoul's troubles with Pyongyang, but had no new ideas for curbing North Korea's nuclear ambitions.

"U.S. cannot exert leadership in Asia only with words," read the headline of an editorial in South Korea's Chosun Ilbo newspaper.

"The summit talks between Korea and the U.S. was no more than symbolic," the Hankook Ilbo newspaper said.

There was also an awkward moment during a news conference with President Park Geun-hye when an American TV reporter asked jokingly whether Obama would save Russian President Vladimir Putin if he saw him drowning.

It was meant as a light-hearted rejoinder to a similar question put to Putin on Russian TV earlier in the month - Obama followed his Kremlin counterpart in saying he would - but drew sharp criticism from South Korean media who saw it as inappropriate in a country mourning hundreds lost on the ferry.

In Manila, Obama hailed one of the few tangible achievements of the trip - the signing of a 10-year military pact with the Philippines that opens the way for U.S. troops, planes and warships to have greater access to bases in the Philippines.

While significantly bolstering the security component of the pivot strategy, the deal, which faced significant political opposition in the former U.S. colony, may be less than meets the eye.

It is more of a legal framework, does not specify how many assets will be permitted on a "rotational basis" and requires decisions on deployments on a mission-by-mission basis, U.S. officials said.

Despite that, Obama appears to have won credit in Southeast Asia, where he also visited Malaysia, for undertaking what was essentially a make-up for a visit he canceled last fall because of a government shutdown.

"This is a part of the world where showing up and giving high-level attention makes a difference," a senior U.S. official said.